An ACAT inhibitor is believed to act on the atherosclerotic lesions to inhibit accumulation of cholesterol esters thereby inhibiting onset and progress of atherosclerosis and also act on the mucosa of the small intestine to inhibit absorption of cholesterol.
It is also considered that an ACAT inhibitor suppresses formation of cholesterol esters in the liver, which leads to reduction in blood cholesterol level (see V. A. Kosykh. et al., Atherosclerosis, Vol. 68, pp. 67-76 (1987)).
Among known ACAT inhibitors, the compounds disclosed in U.S. Pat. No. 4,623,662, JP-A-60-41655, and JP-A-63-253060 (the term "JP-A" as used herein means an "unexamined published Japanese patent application") are structurally similar to the anilide derivatives of the present invention but their ACAT inhibitory action is not sufficient.
An object of the present invention is to provide a compound having a potent ACAT inhibitory activity.